Xerox Corporation

Other

Joannes N M De Jong

Lloyd A Williams

Barry Paul Mandel

Gerald M Fletcher

Peter John Knausdorf

Vittorio R Castelli

Steven Robert Moore

Palghat Srinivas Ramesh

Daniel Clark Park

Thomas Jay Wyble

Liang-Bih Lin

Roger Gaylord Leighton

Daniel W Costanza

Elias Panides

Paul S Bonino

Ruddy Castillo

Injae Choi

Marina L Tharayil

Matthew Dondiego

Bin Zhang

Dusan G Lysy

Vincent M Williams

Rene E Sanchez

Embodiments described herein are directed to a system for reducing electrostatic fields underneath print heads in a direct marking printing system. The system includes: one or more print heads for depositing ink onto a media substrate; a media transport for moving the media substrate along a media path past the one or more print heads; a conductive platen contacting the media transport belt; and an electrostatic field reducer that includes an alternating current corona device positioned upstream of the one or more print heads. The media transport includes a media transport belt and, when the media substrate is on the transport belt it has an electrostatic field, which can cause printing defects. The electrostatic field reducer reduces the electrostatic field on the surface of the media substrate and thereby reduces printing defects.

System and method for reducing electrostatic fields underneath print heads in an electrostatic media transport

In a web printer, tension on the moving web is controlled by monitoring the tension on the web between two rollers and selectively operating an actuator driving the second roller to restore the tension to an acceptable range. The operation of the actuator includes modulating the speed at which the second roller is driven.

Method and device for controlling tension applied to a media web

Embodiments described herein are directed to a reflex printing system with improved image quality. A media transport moves a media substrate or an intermediate belt along a media path in a process direction past the two or more print heads, which deposit inks onto the media substrate or the intermediate belt. A velocity measuring device directly measures and transmits the speed of the surface of belt or media that is to receive the image to a controller, which sends print commands to the two or more print heads to control the frequency of the printing. The inks deposited on the media substrate or intermediate belt have a color registration of from 10 to 20 microns.

Image quality by printing frequency adjustment using belt surface velocity measurement

When tacking print media to a print media transport belt in a printer, a tack module having a pair of nips is employed to control charge migration in across the print media in order to tolerate lead edge curl while ensuring uniform printing. An upstream nip is formed by a first bias transfer roll and a first backup roll, and a downstream nip is formed by a second bias transfer roll and a second backup roll. The respective backup rolls are offset slightly upstream of the respective bias transfer rolls. Charge of opposite polarities is applied to the first backup roll and the second bias transfer roll to facilitate taking of the print media to the print media transport belt.

Media tacking to media transport using a media tacking belt

Embodiments described herein are directed to a system for reducing electrostatic fields underneath print heads in a direct marking printing system. The system includes: one or more print heads for depositing ink onto a media substrate; a media transport for moving the media substrate along a media path past the one or more print heads; a conductive platen contacting the media transport belt; an electrostatic field reducer that includes an alternating current charge device positioned upstream of the one or more print heads; and one or electrically isolated biased electrodes in registration with the ink deposition areas of the one or more print heads. The media transport includes a media transport belt and, when the media is on the transport belt it has an electrostatic field, which can cause printing defects. The electrostatic field reducer and electrodes reduce the electrostatic field on the surface of the media and thereby reduce printing defects.

Active biased electrodes for reducing electrostatic fields underneath print heads in an electrostatic media transport

Provided herein is a document processing system with improved paper path alignment and superior media hold-down capability, which minimizes undesirable electrostatic fields in the print zone. The document processing system includes a first belt module including a first roller and a second roller with a tack belt in surrounding engagement with the first roller and the second roller. The processing system further includes a second belt module, which includes a third roller and a fourth roller with a media transport belt in surrounding engagement with the third roller and the fourth roller. A mounting support for the first belt module is also included herein, the mounting support is designed to allow the first module to self-align relative to the second transport.

Tracking in belt on belt architecture through self-alignment

Provided are vacuum transport systems, methods of making them and methods of transporting one or more objects. In accordance with various embodiments, there is a vacuum transport system including a vacuum plenum and one or more transport members configured to rotate around the vacuum plenum and wherein at least one of the one or more transport members can include a substrate, the substrate including a plurality of holes extending from a first side proximate to the vacuum plenum to a second side proximate to an object, wherein a surface of the second side comprises a textured surface having an average roughness Ra of about 2 &#x3bc;m to about 100 &#x3bc;m.

Surface roughness for improved vacuum pressure for efficient media hold-down performance

A substrate media height detector for a printing system having a print head including a media transport having a surface for moving a sheet of substrate media along a media path in a process direction. An elongate detection member includes a portion extending across the media path in a cross-process direction and is spaced from the media transport surface a predetermined distance. The detection member is movably attached to a support structure and is deflectable upon engagement with a sheet of substrate media. A deflection sensor senses the deflection of the detection member by the substrate media.

Excessive substrate media height detection in a printing apparatus

A system and method for adjusting an electrostatic field in a print zone of an inkjet printer. The printer includes an electrostatic tacking device to hold a sheet of recording media to a transport belt moving through the print zone for imaging with one or more inkjet printheads. A sensor determines the electrostatic field before the print zone and adjusts the electrostatic field with a corotron disposed after the tacking device and before the print zone. Reduction of the electrostatic field in the print zone can reduce imaging errors resulting from electrostatic fields.

System and method for adjusting an electrostatic field in an inkjet printer

Embodiments described herein are directed to a system for reducing velocity transits in a printing system caused by media entering into a transfer nip. The system includes: an imaging drum, a variable speed motor, a transfix roll, a transfix nip, a media transport, a thickness sensor, a skew sensor, a media sensor, a switching means and a controller. Media thickness and/or media skew measurements are used in a feedforward control scheme to increase the imaging drum torque when the media sensor detects a media immediately before it is engaged by the transfer nip.

Motion quality of a transfix nip by media thickness and/or skew feedforward to nip motor torque

A system and method for determining substrate media height including a media transport having a transport surface for carrying thereon substrate media along a media path in a process direction past a print zone. A media height detector is disposed upstream of the print zone. The height detector includes an elongate member disposed above the transport surface and extending across the transport surface in a cross-process direction. The elongate member is slanted with respect to the transport surface with a distance between the elongate member and the transport surface decreasing as the detector extends in the process direction. The height detector includes a deflection sensor operably connected to the elongate member. The deflection sensor senses deflection of the elongate member.

Substrate media height measurement system and method

A printer having an imaging drum rotatable around its longitudinal axis, receives a pattern of ink corresponding to an image to be printed. A transfix roller rotates around its longitudinal axis, and is selectively held against the imaging drum by a transfix force, the interface of the imaging drum and the transfix roll forms a transfix nip. An image is formed on the substrate passed through the transfix nip by the marking ink on the imaging drum. A motor drives the imaging drum through a power train with a speed and direction controlled by a motor drive unit. A substrate sensor detects the substrate at the transfix nip, and outputs a signal to the motor drive. The motor drive varies the torque applied to the imaging drum in response to the signal, to maintain a constant rotational speed of the imaging drum.

Motion quality improvement by feed-forward torque control of imaging drum

Embodiments described herein include a substrate media registration system in a printing system. The registration system can include a deskewing system, a reflexive system, and a controller. The deskewing system is configured to deskew substrate media. The reflexive system is configured to detect the lateral position of the substrate media and at least one of a lead edge and a trail edge of the substrate media being transported in the process direction. The controller is operatively coupled to the reflexive system and is configured to control ejection of ink from a print head system in response to detecting the lateral position of the substrate media and at least one of the lead edge and the trail edge of the substrate media.

Substrate media registration system and method in a printing system

A media transport includes first, second and third media transports to convey a substrate media. A force transducer outputs a force signal associated with a force between the first and second media transports. A sensor outputs a detection signal associated with substrate media being between the second and third media transports. A control unit outputs a first control signal to the first and/or second drive units, dependent upon a comparison of the force signal with a predetermined value. The first control signal commands the first or second drive unit to drive respective first or second media transports to maintain the force signal at or about no greater than the predetermined value. Responsive to the detection signal, the control unit outputs a second control signal in place of the first control signal, commanding the first and/or second drive unit at a predetermined speed.

Motion quality by automatic velocity match between upstream and downstream transports

A media transport apparatus includes a first media transport, having a first transport surface and a first drive unit, to convey the substrate media. A second media transport having a second transport surface and a second drive unit receives the substrate media from the first. A first force transducer outputs a force signal associated with a first force between the media transports. A control unit receives the force signal, and outputs a control signal to at least one of the first and second drive units that is dependent upon a comparison of the first relative force signal with a predetermined value. The control signal commands the first or second drive unit to drive the motion of the respective first or second media transport to maintain the force signal at or about no greater than the predetermined value.

Growing community of inventors

Hopewell Junction, NY, United States of America

Joannes N M De Jong